Lighting problem on a procedural planet

Hi everyone.

I am starting to loose my mind (and days :confused: ) on a lighting problem in UE5.
I started a project to make procedural 3D planets with LOD, and i have a (i guess) normals calculation problem with my procedural mesh that makes the shadows generated by my planet look like the pattern of a tennis ball…

How do you debug lighting issues please ?

If you need the code feel free to ask me. I dont know where to start because i spent too much time on this issue.

Thanks a lot !